The $500 can be in pounds equivalent. I am a UK based Copywriter also in full time employment with an advertising agency called Tribal Resourcing. Having looked at the websites you have listed, some of the issues that need attention include layout of the website itself in order to make them more appealing and easy on the eye to the reader. Better use of space and reduced text content could also help draw people in to the products you are trying to sell. I would suggest that these aspects of the sites are the major areas for attention.
The minor issues include the way some of the web content is worded, some grammatical and spelling issues and sentence configuration. I am UK based as mentioned earlier so all content will be in UK English and about myself, I am advertising executive by profession with a degree in Media and Communication Studies along with 5 years experience in the Media industry. To be honest the work may take me longer than some other bidders but I can guarantee reliability, quality and professionalism to produce well rounded work that is effective for your needs. Many Thanks for the opportunity and I hope my advice proves helpful.